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Operating central locking with transmitter key, function - GF80.20-P-2002LE

MODEL 221.0 /1, 216.3 as of model year 2009 /YoM 08 

Function requirements, general 

Central locking (CL), operation with transmitter key (A8/1) function, general 

The CL can be operated with the transmitter key.

The operation of the transmitter key comprises the following partial functions:

Function sequence for presetting global and selective unlocking 

If the unlock and lock buttons on the transmitter key are pressed simultaneously for t = 5 seconds, a change between the "global" and "selective" settings takes place. The indicator lamp on the transmitter key comes on for confirmation.

Only the driver door and the fuel filler flap are unlocked when the "Unlock" button on the transmitter key is pressed. Only the next actuation of the "Unlock" transmit button unlocks the entire vehicle.

Function sequence for locking or unlocking 

When the "Lock or unlock" button the transmitter key is actuated, it transmits a radio signal via the rear window antenna amplifier module (A2/12) to the rear SAM control unit with fuse and relay module (N10/2). The EIS control unit (N73) receives the signal from the SAM control unit via the interior CAN. Parallel to the radio signal, an infrared signal is transmitted driver door infrared sensor (B58) (precise aiming required). This signal is read in by the left door control unit (N69/1) (on model 216) or left front door control unit (N69/1) (on model 221) and transmitted to the EIS control unit via the interior CAN (CAN B).

IMPORTANT The infrared and radio signals contain the same information (redundant). The first signal received always has priority.

In both cases, the EIS control unit checks the access authorization of the transmitter key.

If the access authorization is valid, the EIS control unit transmits the command "Lock or unlock" via the interior CAN to the following control units:

Model 221:

Model 216:

Moreover, the rear SAM control unit enables or disables the opening request from the trunk lid external switch (S88/8).

IMPORTANT If the driver door is opened during locking, the driver door is not locked An open passenger door is locked

When the vehicle is unlocked, the interior illumination (IBL) is switched on with the soft-on feature by the overhead control panel control unit (N70).

Function sequence for visual feedback (without code (494) USA version) 

After successful locking or unlocking, the turn signal lamps flash as visual feedback.

The function is controlled by the rear SAM control unit, transmitting the turn signal as blinkmaster with the interior CAN:

IMPORTANT For further information on visual feedback see separate function description on exterior lights.

If a door is still open when locking, there is no visual feedback.

Function sequence for acoustic feedback (as of 1.9.10) 

Select and activate acoustic feedback in instrument cluster (A1) via left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111).

The status of the acoustic feedback is transmitted by the instrument cluster via the central CAN (CAN F) to the central gateway control unit (N93) and from there to the front fuse and relay module control unit (N10/1) via the interior CAN. If the acoustic feedback function is activated and the successful locking and unlocking, an acoustic feedback is output by momentarily actuating the left horn (H2) and right horn (H2/1).

If the transmitter key is valid and the acoustic feedback activated, the EIS control unit transmits the command "Lock or unlock" via the interior CAN to the front SAM control unit, which momentarily actuates the horns via the horn relay (N10/1kF).

IMPORTANT If a door is still open when locking, there is no acoustic feedback.

Function sequence for trunk lid remote opening 

When the "Remote trunk release" is actuated, the transmitter key transmits the corresponding signal. The data flow is the same as described previously for "Locking or unlocking".

However, only the trunk lid CL motor is actuated by the rear SAM control unit to unlock the trunk lid. The remaining CL remains deactivated.

After closing, the trunk lid it is relocked.

Function sequence for mechanical trunk lid locking (with code (887) Valet Parking) 

The trunk lid can be secured mechanically by locking with the emergency key. The position of the trunk lid is relayed to the rear SAM control unit by the trunk lid contact switch (S88/6). The opening request from the rear SAM control unit is enabled or disabled according to the position.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for central locking, operation with transmitter key Model 216 PE80.20-P-2052-97CAA
Model 221 PE80.20-P-2052-97SAA
  Component description for instrument cluster A1
Model 216.3, model 221 (except 221.095/195)		 GF54.30-P-6000LE
Model 221.095/195 GF54.30-P-6000LEH
  Component description for front SAM control unit with fuse and relay module N10/1 GF54.21-P-6070LE
  Component description for rear SAM control unit with fuse and relay module N10/2 GF54.21-P-6030LE
  Component description for left door control unit N69/1
Model 216		 GF72.29-P-4124LA
  Component description for left front door control unit N69/1
Model 221		 GF72.29-P-4141LE
  Component description for right door control unit N69/2
Model 216		 GF72.29-P-4128LA
  Component description for right front door control unit N69/2
Model 221		 GF72.29-P-4142LE
  Rear door control unit, component description N69/3, N69/4
Model 221		 GF72.29-P-6020LE
  EZS control unit, component description N73 GF80.57-P-6003LE 
  Component description for steering column tube module N80 GF54.21-P-6050LE
  Component description for central gateway control unit N93 GF54.21-P-4170LE
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